Donald Trump’s erratic posture on trade is forcing Japanese policymakers to rethink their reliance on the economic and political alliance with the United States, according to a former high-level diplomat from the Office of the U.S. Trade Representative.

Wendy Cutler, former acting deputy U.S. Trade Representative, explained that recent Japanese trade initiatives, such as the newly negotiated Comprehensive and Progressive Agreement for Trans-Pacific Partnership, are concrete examples of Japan’s drive to diversify trade relationships and “hedge” against a decline in U.S. influence and power in Asia.

“I think Japan has learned that Trump is unpredictable. You may be his best friend one day, but a week later he is complaining about Japanese trade,” Cutler said in an interview Saturday. She is familiar with Tokyo’s trade policy through her negotiations with Japanese diplomats over the original TPP trade deal.